Pinpoint Test AF: DTC U0121 - Lost Communication With Anti-Lock Brake System Control Module (Abs)

AF1 RETRIEVE THE RECORDED DTCs FROM BOTH THE CONTINUOUS AND ON-DEMAND INSTRUMENT CLUSTER (IC) SELF-TESTS
- Check for recorded instrument cluster (IC) DTCs from the continuous and on-demand self-tests.
- Is DTC B1318 recorded?
1. YES : Go to Pinpoint Test AB .
2. NO : Go to AF2.
AF2 RECHECK THE INSTRUMENT CLUSTER (IC) DTCs
- Key in ON position.
- Enter the following diagnostic mode on the diagnostic tool: Instrument Cluster (IC) Self-Test
- Clear the DTCs. Repeat the instrument cluster (IC) self-test.
- Is DTC U0121 still present?
1. YES : Go to AF3.
2. NO : The system is operating correctly at this time. The DTC may have been set due to high network traffic.
AF3 CHECK THE PCM FOR DTC U0121
- Carry out the self-test on the PCM.
- Is DTC U0121 retrieved?
1. YES : REFER to MODULE COMMUNICATIONS NETWORK article to diagnose no communication with the ABS module.
2. NO : Go to AF4.
AF4 CHECK FOR CORRECT INSTRUMENT CLUSTER (IC) OPERATION
- Disconnect the instrument cluster (IC) connector.
- Check for:
  - corrosion
  - damaged pins
  - pushed-out pins
- Connect the instrument cluster (IC) connector and make sure it seats correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
1. YES : INSTALL a new instrument cluster (IC). REFER to Instrument Cluster (IC) . TEST the system for normal operation.
2. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.